SPIRAL TWINERS. 17 



(Dicotyledons, continued.) 



Hoy a carnosa (Asclepiadacese) made several circles in from 16 b. to 22 h. 

 or 24h. 



Convolvulus major (Convolvulaccfie) moves against the sun. Plant placed in 

 room with lateral light. 



1st circle... 2 h. 42 m. | ^^^^^'''^^^^ ^^T ^^*^* ^^ ^^' ^^^'* *^ ^'^*^ 



L 1 h. 28 m. : difference 14 m. 



2nd circle... 2 h. 47 m. j ^^"^^^^^^^®' ^^^ ^'^^'^ in Ih. 17 ra., to light 



1 1 h. 30 m, : difference 13 m. 



Convolvulus septum (large -flowered cultivated var.) moves against the sun. 

 Two circles, each in 1 h. 42 m.: difference in semicircle from and to light 14 m. 



Ipomcea jucunda (Convolvulaceee) moves against the sun, placed in my study, 

 with windows feeing the north-east. Weather hot. 



1st circle 5 h. 30 m fSemicircle, from light in 4h. 30m., to light 



L 1 h. m. : difference 3 h. 30 m. 



2nd circle 5 h. 20m. (Lat^ ] ^ . . , „ v w . o i. r/^ i. i- i.^ 



ft. -1 Semicircle, from light m 3h. 50 m., to light 



m afternoon: circle com-}- ,. „ _ ' ..^ ^t «^ 



1^1*^ Ac^x. ^ .\ Ih. 30 m.: difference 2 h. 20 m. 



pleted at 6 m. 40 h. P.M.) ) 



We have here a remarkable instance of the power of hght in retarding and 

 hastening the revolving movement. 



Sivea tilicBfolia (Convolvulacea)) moves against the sun, and made four revo- 

 lutions in 9 h. ; so that each, on average, was performed in 2 h. 15 m. 



Plumiago rosea (Plumbaginaccse) follows the smi. The shoot did not begin 

 to revolve mitil nearly a yard in height ; it then made a fine circle in 10 b. 45 m. 

 Duruig the next few days it continued to move, but irregularly. On August 15th 

 the shoot followed, dmung a period of lOh. 40m., a long and deeply zigzag course 

 and then made a broad ellipse. The figure thus traced altogether apparently 

 represented three ellipses, each of which averaged 3 h. 33 m. for its completion. 



Jasminum patt^iJlorum^^QnihsLm (Jasminacese), moves against tlie sun. First 

 circle in 7h. 15 m., second circle rather more quickly. 



Clerodendrum Thomsonii (Verbenaceee) follows the sun. 



April 12, 1st circle 5 45 (shoot very yoimg). 



„ 14,2nd „ 3 30 



„ 18, semicircle 5 (directly aflcr the plant was shaken in 



„ 19, 3rd circle 3 [being moved). 



„ 20,4th „ 4 20 



against 



h. m. [ h. m. 



March 17, 1st circle 6 30 March 22, 3rd circle 8 30 (very cold 



„ 19,2nd „ 7 I „ 24,4th „ 6 45 [day). 



Thunhergia alata (Acantliacese) moves against sun. 



n. m. 



pril 14, Ist circle 3 20 

 „ 18, 2nd „ 2 50 



?» 



h. m. 



IS, 3rd circle 2 55 [noon). 



18, 4th „ 3 55 (1»^ in a<^*"''- 



tlmccie) follows the sim. A young fhoot made 



LIKF. PEOC. — BOTANY, TOL. IX. 



